Facsimile machine having resolution compatible with data terminal device

ABSTRACT

The facsimile machine connected with a personal computer such that it can send image data to the personal computer. The facsimile machine first requests the personal computer to supply data about communication capability of the personal computer such as resolution mode (scanning line density) and coding method to the personal computer. Upon this request, the personal computer outputs necessary data to the facsimile machine. If a user of the facsimile machine sets to scan the image at a resolution finer than a resolution of the personal computer, then resolution is automatically changed to a rougher resolution to conform with the personal computer. The facsimile machine then scans the image at the modified resolution. The scanned image is coded by the same coding method as the personal computer. The image scanned and coded in line with the communication capability of the personal computer is then stored in a memory and transmitted to the personal computer from the memory.

BACKGROUND OF THE INVENTION

1. Technical Field

The present invention relates to a facsimile machine to which a dataterminal device such as a personal computer is connected.

2. Background Art

Facsimile machines are able to send and receive arbitrary image data toand from a remote communication device so that they are widely used inoffices and homes. On the other hand, data terminal devices such aspersonal computers having many functions are also developed. In recentyears, a personal computer is connected to a facsimile machine as a dataterminal device to provide a facsimile-personal computer system. In thiscombined system, the facsimile machine and personal computer areoperable in a cooperative manner.

In this facsimile-personal computer system, the facsimile machine canfunction as a scanner for the personal computer if it is used to scan animage and send it to the personal computer. The personal computer thenmodify or process the image data. The facsimile machine can alsofunction as a printer for the personal computer if it is used to receiveimage data from the personal computer, which image data is prepared bythe personal computer, and print it on a recording sheet. The facsimilemachine can further function as a modem for the personal computer if itis used to receive and send image data from and to a remotecommunication device since the facsimile machine is connected to theremote communication device via a communication line and is able toperform facsimile communication between the remote communication deviceand itself.

When the above described conventional facsimile machine is used as ascanner for the data terminal device such as a personal computer,communication capability of the personal computer (e.g., how thepersonal computer receives data from the associated facsimile machine)is generally unknown. Accordingly, the conventional facsimile machinehas the following problems.

Before sending image data to the personal computer from the facsimilemachine, the facsimile machine scans the image, codes it, stores it inits memory, and conducts handshaking with the personal computer toconfirm communication capability of the personal computer. Therefore, ifscanning resolution (or scanning line density) of the facsimile machineis finer than the communication capability of the personal computer(e.g., if the facsimile machine scans the image at high resolution butthe personal computer does not have such a high resolution), the dataform should be adjusted to a lower resolution before data transmissionto the personal computer so that it conforms with the communicationcapability of the personal computer.

Specifically, if the facsimile machine scans the image at a superfinemode (15.4 lines/mm line density) but the personal computer only has afine mode (3.85 lines/mm line density), then the image which has beenscanned, coded and stored by the facsimile machine should be coded againsuch that the image data to be transmitted matches the resolution of thepersonal computer. Thus, the processing for image data transmission tothe personal computer is complicated and time consuming.

SUMMARY OF THE INVENTION

The present invention was developed in consideration of the aboveproblems of the conventional facsimile machine, and an object of thepresent invention is to provide a facsimile machine which can send animage to a data terminal device in an effective manner by knowingcommunication capability of the data terminal device beforehand.

According to one aspect of the present invention, there is provided afacsimile machine of a type which is connectable with a data terminaldevice and which is able to scan an image, code resulting image data,store the coded image data in a memory and send the coded image to thedata terminal device from the memory, characterized in that thefacsimile machine includes storage means for storing data aboutcommunication capability of the data terminal device and control meansfor scanning the image and coding the image data based on the data aboutthe communication capability of the data terminal device stored in thestorage means.

The data about the communication capability of the data terminal deviceis first stored in the storage means. After that, the data scanning andcoding are carried out using this data. Specifically, image scanning bythe facsimile machine is carried out at the same scanning resolution(line density) as the data terminal device if the scanning resolution ofthe facsimile machine is finer than the data terminal device, and theimage data coding is carried out by the same coding method as the dataterminal device if the coding method of the facsimile machine is anadvanced one (or more complicated one) than the data terminal device.Therefore, it is unnecessary to convert the image data to another dataform compatible with the data terminal device after storing the imagedata in the memory of the facsimile machine even if the data receivingdevice (data terminal device) has an inferior communication capabilitythan the data sending device (facsimile machine of the invention). As aresult, the processing for data transmission to the data terminal deviceis simplified and the time required for data transmission is reduced ascompared with the conventional facsimile machine. The communicationcapability of the data terminal device is capability used forcommunication with the facsimile machine of the invention and itincludes, for example, coding capability and recording capability asdescribed above.

If there is no data about the communication capability of the dataterminal device in the storage means, the control means mayautomatically request the data terminal device to supply such data.After acquiring the necessary data from the data terminal device andstoring it in the storage means, the facsimile machine scans the imageaccording to the known communication capability of the data terminaldevice.

If communication capability of the facsimile machine is superior to thatof the data terminal device, the process from the data scanning to thedata storage into the memory is carried out based on the communicationcapability of the data terminal device. Therefore, the data transmissionto the data terminal device from the memory of the facsimile machinerequires no modification even if the sending and receiving devices havedifferent communication capabilities. In general, the facsimile machinepossesses a higher performance. In such a case, the image scanning isautomatically performed according to the performance of the dataterminal device (by using a rougher resolution and a less complicatedcoding method). No matter how the image scanning manner and codingmethod are set by a user or the facsimile machine, these are changed toconform with the communication capability of the data terminal device ifthe communication capability of the facsimile machine is superior tothat of the data terminal device.

Additional objects, aspects and advantages of the present invention willbecome apparent to those skilled in the art to which the inventionrelates from the following detailed description of preferred embodimentsand the appended claims as read in conjunction with the accompanyingdrawings.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

FIG. 1 is a block diagram showing major parts of a facsimile machineaccording to the present invention;

FIG. 2 is a perspective view of a communication system including thefacsimile machine shown in FIG. 1 and a personal computer;

FIG. 3 is a diagram illustrating a series of operations performed by thefacsimile machine and personal computer with data and signals exchangedto determine communication capability of the personal computer;

FIG. 4 is a flowchart showing the operations of the facsimile machinewhich corresponds to the diagram of FIG. 3; and

FIG. 5 is a flowchart of another series of operations executed by thefacsimile machine to illustrate how communication capability of thefacsimile machine of the invention is adjusted in view of communicationcapability of the data terminal device prior to image scanning.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Now, a preferred embodiment of the present invention will be describedwith reference to the accompanying drawings.

Referring to FIG. 2, illustrated is a schematic diagram of acommunication system including a facsimile machine F of the inventionand a personal computer PC. The facsimile machine F is connected to thepersonal computer PC (i.e., data terminal device) via a communicationline L according to RS-232C standard, for example, and connected to atelephone line or network via another communication line La. Thefacsimile machine F of this facsimile-personal computer system canperform facsimile data communication via the telephone line La and canserve as a modem, printer and scanner for the personal computer PC.

It should be noted that the data terminal device is not limited to thepersonal computer PC, but it may be any suitable communication device aslong as it can communicate with the facsimile machine F. For instance, acommunication device which operates on a standard protocol ofAsynchronous Facsimile DCE Control Standard Service Class 1 (simplyreferred to as "Service Class 1") (EIA/TIA-578) may be employed. InService Class 1, the data terminal device defines a command to set andcontrol the facsimile machine F and a response which the facsimilemachine F outputs in response to this command, and the command andresponse are serially exchanged through the communication line L toenable data transmission to the facsimile machine F from the dataterminal device PC and vice versa.

Referring now to FIG. 1, illustrated is an example of a basicconfiguration of the facsimile machine F. A reference numeral 1 denotesCPU for various signal controlling, 2 NCU for sending a dialing signalto the communication line La, 3 a modem for modulating and demodulatingsignals to receive and send facsimile image data from and to a remotefacsimile machine (not shown), 4 a control panel including variousoperation switches and keys such as numeric keys as well as a displayunit such as LCD, 5 a scanner for scanning a document (or an image) tobe transmitted to the remote facsimile machine via the line La or to thepersonal computer PC via the line L, 6 a system memory including ROM forstoring programs used by CPU and RAM for temporarily storing variousdata, 7 an image memory for storing image data sent from the personalcomputer PC via the communication line L, image data sent from theremote facsimile machine via the telephone line La and image datascanned by the scanner 5, 8 a codec for coding and decoding the imagedata according to MH or MR method, 9 an image processing unit forapplying a resolution change process, a size reduction/magnificationprocess and a smoothing process to the image data after decoding by thecodec 8, 10 a printer for printing the image data on a recording sheet,and 11 a communication controller for controlling communication betweenthe personal computer PC and facsimile machine F via the communicationline L according a predetermined protocol.

An initial setting of the facsimile machine F is performed by signalssupplied from the personal computer PC via the communication controller11.

In a normal mode, if the facsimile machine F receives data from a remotefacsimile machine via the telephone line La, the data is simplytransferred to the personal computer PC, and if the facsimile machine Freceives data from the personal computer PC, the data is transmitted toa designated destination via the telephone line La after making a callbased on dialing data about a facsimile number of the destination sentfrom the personal computer PC. If the facsimile machine F scans an imageby its scanner 5, the data is coded by the codec 8, stored in the imagememory 7 and sent to the personal computer PC from the image memory 7.

In the present invention, the communication capability of the personalcomputer PC is already known before handshaking is conducted in a seriesof data transmission processes. The communication capability of thepersonal computer PC is capability needed to communication with thefacsimile machine F (i.e., data reception capability of a communicationsoftware loaded in the personal computer PC), which includes a codingmethod and a processing capability in recording such as a line density.

CPU 1 makes a request to the personal computer PC via the communicationcontroller 11 to know communication capability of the personal computerPC as a user of the facsimile machine F operates a particular key on thecontrol panel 4 (unshaded arrow (1)). Upon this request, the personalcomputer PC sends data about its communication capability to thefacsimile machine F (unshaded arrow (2)). This data is then stored in,for example, RAM of the system memory 6 (unshaded arrow (3)). Thefacsimile machine F conducts communication with the personal computer PCusing this data.

As described above, when the personal computer PC is connected to thefacsimile machine F for the first time, the facsimile machine F onceasks the personal computer PC to send the communication capability datato the facsimile machine F. The facsimile machine F stores this data andutilizes it in subsequent data transmission to the personal computer PC.Therefore, even if communication capability of the personal computer PCis different from that of the facsimile machine F, processing for thedata transmission is carried out in conformity with the communicationcapability of the personal computer PC. In other words, it isunnecessary for the facsimile machine F to change the data form afterstoring the image data in the image memory 7 or after handshaking withthe personal computer PC.

In the illustrated embodiment, the facsimile machine F obtains thecommunication data about the personal computer PC according to a normalhand shaking process (T-30) upon operation of the control panel 4. Itshould be noted, however, that particular commands may be used toconduct the data request (1) and reply (2).

FIG. 3 illustrates a series of processing (1) to (6) executed by thefacsimile machine F and personal computer PC with signals and dataexchanged between the facsimile machine F and personal computer PC toacquire the data about the communication capability of the personalcomputer PC. This is conducted before the image data is transmitted tothe personal computer PC from the facsimile machine F. FIG. 4illustrates a flowchart for the facsimile machine F (Steps 100 to 105)operating in accordance with the diagram shown in FIG. 3.

As a user operates the control panel 4, the facsimile machine F makes acall to the personal computer PC (RING). Upon receiving the call, thepersonal computer PC outputs a reception acknowledge signal or commandand subsequently various data such as CSI (Called SubscriberIdentification) and DIS (Digital Identification Signal). Using DIS, thefacsimile machine F analyzes a coding method (MH, MR or the like), linedensity (normal, fine or superfine), a communication speed and the like,and stores analyzed data in the system memory 6. Then, the facsimilemachine F sends DCN (Disconnection) signal to automatically terminatethis process.

It should be noted that the timing when the facsimile machine F acquiresthe data about the communication capability of the personal computer isnot limited to upon the user's operating the control panel 4. Forexample, if there is no data in the system memory 6 about thecommunication capability when the scanner 5 scans a document to be sentin the form of image data to the personal computer PC, then thefacsimile machine F automatically may start the above describedcommunication capability data acquisition process.

In this manner, the communication performance of the personal computerPC is known upon manual operation of the control panel 4 orautomatically before the facsimile machine F starts the image datascanning. This is particularly useful when the data is stored once inthe memory 7 of the facsimile machine F before transmitted to thepersonal computer PC. Specifically, by sending a request to the personalcomputer PC about the communication capability data prior to image datascanning, the facsimile machine F can scan and code the image data inconformity to the communication capability of the personal computer PCand store it in the image memory 7. Unlike the conventional facsimilemachine, therefore, the facsimile machine of the present invention willnot need to reformat the scanned image data stored in the image memory 7in order to step down to the PC's communication capability.

If it is determined from the series of operations shown in FIG. 3 thatthe illustrated facsimile machine F of the present invention F has asuperior communication capability than the personal computer PC, thendata transmission to the personal computer PC from the facsimile machineF is carried out according to the communication capability of thepersonal computer PC.

A series of operations executed by the facsimile machine F to start theimage scanning with an appropriate scanning mode or resolution and thecoding by an appropriate coding method is illustrated in the flowchartof FIG. 5 (Steps 200 to 204) using a concrete example.

In FIG. 5, it should be assumed that the personal computer PC has thefollowing capability: line density is fine and the coding method is MRmethod. On the other hand, the facsimile machine F is able to scan animage with the normal or superfine line density.

If the line density of the facsimile machine F is set to normal by auser, the line density of the personal computer PC (i.e., fine) is finerthan normal so that the communication capability of the facsimilemachine F is not superior to that of the personal computer PC. In thiscase, the scanning line density is not changed from normal since it isnot beyond the communication capability of the personal computer PC. Thescanning by the scanner 5 is performed according to MR coding methodsince it is the coding method of the personal computer PC. After imagescanning and coding, the image data is stored in the image memory 7.

If the user selects a superfine mode, the communication capability ofthe facsimile machine F is superior to that of the personal computer PCin line density. In such a case, the image scanning is performed in linewith the line density of the personal computer PC (i.e., fine mode). Inshort, the line density is changed to fine from superfine. The codingmethod employed by the scanner 5 is MR since this is the coding methodof the personal computer PC. After scanning and coding under theseconditions, the image data is stored in the image memory 7.

After stored in the image memory 7, the image data is sequentially readout or retrieved from the image memory and transmitted to the personalcomputer PC via the communication controller 11. Since the image dataalready conforms to the communication capability of the personalcomputer PC, it is not necessary to convert the image data to aparticular form after reading out from the image memory 7.

If the communication capability of the personal computer PC is notstored in the system memory 6, the line density is set to normal and theMH coding method is used in the scanning process regardless of thescanning mode and coding method setting made by the user or facsimilemachine F (Step 204). The normal line density and MH coding method arethe least or minimum communication capability which any personalcomputers possess. Therefore, the image data to be transmitted to thepersonal computer PC does not need any conversion when transmitted tothe personal computer PC from the image memory 7 of the facsimilemachine F.

What is claimed is:
 1. A facsimile machine connected with a dataterminal device such that it can scan an image, store the image in amemory and send the image to the data terminal device from the memory,the facsimile machine being adapted to operate on one of a plurality ofseries of predetermined processes from image scanning to image storage,the facsimile machine comprising:storage means for storing data aboutcommunication capability of the data terminal device includingresolution for image scanning and data storing; and control means forselecting one of the plurality of series of predetermined processesbased on the data about the communication capability of the dataterminal device stored in the storage means and for causing thefacsimile machine to operate on the selected series of processes, storeddata being sent to the data terminal device without resolutionconversion.
 2. The facsimile machine of claim 1, wherein if there is nodata about the communication capability of the data terminal device inthe data storage means, the control means requests the data terminaldevice to supply the communication capability data and stores it in thestorage means.
 3. The facsimile machine of claim 1, wherein ifcommunication capability of the facsimile machine is superior to thecommunication capability of the data terminal device, the control meansselects one of the plurality of series of processes which conforms withthe communication capability of the data terminal device.
 4. Thefacsimile machine of claim 1, wherein the communication capabilityincludes line density for image scanning and a coding method.
 5. Thefacsimile machine of claim 2, wherein the communication capabilityincludes line density for image scanning and a coding method.
 6. Thefacsimile machine of claim 3, wherein the communication capabilityincludes line density for image scanning and a coding method.
 7. Thefacsimile machine of claim 6, wherein if the scanning line density ofthe facsimile machine is finer than the scanning line density of thedata terminal device, the control means causes the facsimile machine toscan the image at the scanning line density of the date terminal device.8. The facsimile machine of claim 6, wherein if a coding method of thefacsimile machine is more complicated than that of the data terminaldevice, the control means causes the facsimile machine to code the imageby the coding method of the data terminal device.
 9. The facsimilemachine of claim 1, wherein if there is no data about the communicationcapability of the data terminal device in the data storage means, thecontrol means causes the facsimile machine to scan the image in a normalmode and to code the image data by MH method.
 10. The facsimile machineof claim 1, wherein the data terminal device is a personal computer. 11.A facsimile machine connected with a data terminal device such that itcan send an image to the data terminal device, comprising:first dataacquisition means for acquiring first data about resolution or scanningline density of the data terminal device; a scanner for scanning theimage to provide image data from the scanned image; first control meansfor causing the scanner to scan the image at the resolution or linedensity acquired by the first data acquisition means or a predeterminedresolution or line density depending upon comparison of the first datawith the predetermined resolution or line density; coding means forcoding the image data by a predetermined coding method; a memory forstoring the coded image data; and data transmission means for sendingthe coded image data to the data terminal device from the memory; theacquiring of first data by the first data acquisition means occurring inresponse to a request made to the data terminal device independently ofsending of the coded image data to the data terminal device by the datatransmission means.
 12. The facsimile machine of claim 11 furtherincluding:second data acquisition means for acquiring a coding methodwhich the data terminal device employs; and second control means forcausing the coding means to code the image data by the coding methodacquired by the second data acquisition means or by the predeterminedcoding method depending upon comparison of the coding method known bythe second data acquisition means with the predetermined coding method.13. The facsimile machine of claim 11, wherein if the resolution orscanning line density of the data terminal device as acquired by thefirst data acquisition means is rougher than the predeterminedresolution or scanning line density of the scanner, the first controlmeans causes the scanner to scan the image at the resolution or scanningline density acquired by the first data acquisition means.
 14. Thefacsimile machine of claim 12, wherein if the predetermined codingmethod of the coding means is more complicated than the coding method ofthe data terminal device as acquired by the second data acquisitionmeans, the second control means causes the coding means to code theimage data by the coding method as acquired by the second dataacquisition means.
 15. The facsimile machine of claim 11, wherein thefirst data acquisition means acquires the first data before handshakingwith the data terminal device.
 16. The facsimile machine of claim 12,wherein the second data acquisition means acquires the coding method ofthe data terminal device before handshaking with the data terminaldevice.
 17. The facsimile machine of claim 11, wherein the data terminaldevice is a personal computer.
 18. The facsimile machine of claim 11,wherein the first data acquisition acquires the first data from adigital identification signal (DIS) sent from the data terminal device.19. The facsimile machine of claim 12, wherein the second dataacquisition acquires the coding method of the data terminal device froma digital identification signal (DIS) sent from the data terminaldevice.